1. Field of the Invention
The present invention relates to a manually operated hammer drill and/or paving breaker according to the preamble of patent claim 1.
2. Description of Related Art
Hammer drills and/or paving breakers, hereinafter briefly designated “hammers,” are manufactured in accordance with many different constructive designs, depending on their intended use. Hammers having low electrical power consumption and light weight are generally realized in “pistol form,” having a handle. However, if higher performance demands are made on a hammer of this sort, a correspondingly enlarged diameter of an electric motor (generally a standard universal motor) used in the hammer leads to a disadvantageous large spacing between a percussion mechanism axis and the handle. As a consequence, in hammers having greater electrical power consumption that are built according to this design, this sizable axial displacement leads to a disadvantageous position of the center of gravity, and to excessive pitching vibrations, resulting in worsened handling of the hammer.
In order to improve the handling of a hammer having at least moderate electrical power consumption, a different constructive design is known that provides what is known as a spade handle in the area of the percussion mechanism axis, so that the above-mentioned axial displacement assumes only a small value. However, the standardly used universal motors, with collectors, have a relatively long axial length, which, given a positioning of these motors behind a percussion mechanism of the hammer, would lead to a large overall length of the hammer, again adversely affecting the handling of the hammer for the operator. For this reason, up to now it has been standard in larger hammers of this power class to situate the universal motors exclusively perpendicular to the percussion or drill axis.